<template>
    <div ref="wrapper">
        <slot></slot>
    </div>
</template>

<script>
import BScroll from 'better-scroll'

export default {
    name: "Scroll",
    props: {
        probeType: {
            type: Number,
            default: 1
        },
        data: {
            type: Array,
            default: () => {
                return []
            }
        },
        pullUpLoad: {
            type: Boolean,
            default: false
        }
    },
    data () {
        return {
            scroll: {}
        }
    },
    mounted () {
        setTimeout(this.__initScroll, 20)
    },
    methods: {
        __initScroll () {
            // 1.初始化BScroll对象
            if (!this.$refs.wrapper) return
            this.scroll = new BScroll(this.$refs.wrapper, {
                probeType: this.probeType,
                click: true,
                pullUpLoad: this.pullUpLoad
            })

            // 2.将监听事件回调
            this.scroll.on('scroll', pos => {
                this.$emit('scroll', pos)
            })

            // 3.监听上拉到底部
            this.scroll.on('pullingUp', () => {
                console.log('上拉加载');
                this.$emit('pullingUp')
            })
        },
        refresh () {
            this.scroll && this.scroll.refresh && this.scroll.refresh()
        },
        finishPullUp () {
            this.scroll && this.scroll.finishPullUp && this.scroll.finishPullUp()
        },
        scrollTo (x, y, time) {
            this.scroll && this.scroll.scrollTo && this.scroll.scrollTo(x, y, time)
        },
        getScrollY () {
            return this.scroll ? this.scroll.y : 0
        }
    },
    watch: {
        data () {
            setTimeout(this.refresh, 20)
        }
    }
}
</script>

<style scoped>
</style>
